From 3e51c8c2ff0d5980afa0c9b4f2227bdd59f7befe Mon Sep 17 00:00:00 2001
From: Demian Ferreiro <epidemian@gmail.com>
Date: Sat, 18 Jun 2016 07:37:53 -0300
Subject: [PATCH] Remove unloaders when root element is removed

When a controller calls preventDefault on its onunload method, it prevents the current root element from being unmounted via a route change. But it does not prevent it from being unmounted via m.mount(root, null). In that case, the root element is unmounted, but any unloaders that it had keep hanging on the `unloaders` array, and that prevented any future m.mount(root, component) calls from succeeding. This is what was happening on the pending route() tests.

The fix is pretty simple: just reset the `unloaders` array when removing the root element, just like it's done when no unloader calls preventDefault.

Also, 2 of the 4 pending tests were removed because they were identical to the other 2.
---
 mithril.js            |  1 +
 test/mithril.route.js | 66 ++-----------------------------------------
 2 files changed, 3 insertions(+), 64 deletions(-)

diff --git a/mithril.js b/mithril.js
index e0b464cc..a0877dad 100644
--- a/mithril.js
+++ b/mithril.js
@@ -1473,6 +1473,7 @@
 		components.splice(index, 1)
 		reset(root)
 		nodeCache.splice(getCellCacheKey(root), 1)
+		unloaders = []
 	}
 
 	var redrawing = false
diff --git a/test/mithril.route.js b/test/mithril.route.js
index 7317d268..76ac5c09 100644
--- a/test/mithril.route.js
+++ b/test/mithril.route.js
@@ -102,8 +102,7 @@ describe("m.route()", function () {
 		expect(route2).to.equal("/test13")
 	})
 
-	// FIXME: this causes others to fail
-	xdit("skips route change if component ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
+	dit("skips route change if component ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
 		mode("search")
 		var spy = sinon.spy()
 
@@ -130,68 +129,7 @@ describe("m.route()", function () {
 		expect(spy).to.not.have.been.called
 	})
 
-	// FIXME: this causes others to fail
-	xdit("skips route change if subcomponent ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
-		mode("search")
-
-		var spy = sinon.spy()
-
-		var subsub = {
-			controller: function () {
-				this.onunload = function (e) { e.preventDefault() }
-			},
-			view: function () {
-				return m("div")
-			}
-		}
-
-		var sub = pure(function () { return subsub })
-
-		route(root, "/a", {
-			"/a": pure(function () { return sub }),
-
-			"/b": {
-				controller: spy,
-				view: noop
-			}
-		})
-
-		route("/b")
-
-		expect(spy).to.not.have.been.called
-	})
-
-	// FIXME: this causes others to fail
-	xdit("skips route change if non-curried component ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
-		mode("search")
-
-		var spy = sinon.spy()
-
-		var sub = {
-			controller: function () {
-				this.onunload = function (e) { e.preventDefault() }
-			},
-			view: function () {
-				return m("div")
-			}
-		}
-
-		route(root, "/a", {
-			"/a": pure(function () { return sub }),
-
-			"/b": {
-				controller: spy,
-				view: noop
-			}
-		})
-
-		route("/b")
-
-		expect(spy).to.not.have.been.called
-	})
-
-	// FIXME: this causes others to fail
-	xdit("skips route change if non-curried subcomponent ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
+	dit("skips route change if subcomponent ctrl.onunload calls preventDefault", function (root) { // eslint-disable-line
 		mode("search")
 
 		var spy = sinon.spy()